Japan's nuclear disarmament and nonproliferation policy is comprised of four main pillars:

1. The Atomic Energy Basic Law of 1955—which restricts Japan's nuclear energy use exclusively to peaceful purposes;
2. The "Three Non-Nuclear Principles" adopted in 1968 by the Japanese Diet, in which Japan pledges not to manufacture, possess, or permit the introduction of nuclear weapons onto Japanese soil;
3. Tokyo's compliance with the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and its active participation in strengthening the NPT regime; and
4. Tokyo's reliance on the U.S. extended nuclear deterrent.

Despite Japan's long-standing stance against nuclear weapons, there was an internal debate in the late 1960s through the early 1970s about whether Japan should sign the NPT, in part due to concerns about assuring access to nuclear technology to meet national energy needs, and the discriminatory nature of the treaty. Some conservatives were also concerned that closing off the nuclear option might negatively impact future national security needs. In 1968, then Prime Minister Sato commissioned a secret nongovernmental study on the costs and benefits to Japan of developing nuclear weapons capabilities. The existence of this report was leaked to the public in 1994. The report concluded that nuclearization would negatively affect Japanese security and that the U.S. extended nuclear deterrent would be sufficient. [1]

Japan's political power shift after the general election in August 2009, when the Democratic Party of Japan (DPJ) defeated the Liberal Democratic Party (LDP) that had dominated Japan's politics over the last half century, generated speculation that the new Japanese government might take a more progressive nuclear disarmament policy. Before the election, the LDP was in the process of preparing the country's new National Defense Program Guidelines (NDPG), presumed to include a more assertive security policy. However, due to the political power shift, the DPJ postponed the adoption of the NDPG until the end of 2010 for further consideration. The new NDPG, for the first time since 2004, and the first one published under the DPJ government, introduced a major shift in the country's strategic concept from "basic defense force" to "dynamic defense capability" in response to a rapid transformation of the security environment in the region. These include the ongoing and increasing threats posed by North Korea's nuclear and missile programs, and concerns over China's military modernization and naval activities in the East China Sea. [2] However, Japan's nuclear nonproliferation and disarmament policy so far remains the same, namely that "Japan will play active role in international nuclear disarmament and nonproliferation efforts, and will continue to maintain and improve credibility of U.S. extended deterrence, with nuclear deterrent as a vital element, through close cooperation with the U.S." [3]

While no significant change has yet been observed in Japan's nuclear disarmament policy under the DPJ government, then-DPJ Foreign Minister Katsuya Okada ordered a probe into the secret agreement between Japan and the United States concluded in 1969 that allowed the United States to bring nuclear weapons into Okinawa in case of emergency. Under the earlier LDP administrations, the existence of the secret agreement had been denied for decades. [4] Given that this secret agreement contradicts one of the Three Principles, non-introduction of nuclear weapons to Japan, the issue of the Three Non-Nuclear Principles was rekindled when the existence of the secret agreement was ascertained by the DPJ government.

During the preparation period of the new NDPG, debates over the Three Non-Nuclear Principles, and particularly the third principle of non-introduction, intensified. In the past, hawkish politicians and scholars often advocated reconsidering the non-introduction principle, although successive Prime Ministers have expressed their official support for it. An expert panel, which was formed to prepare the new NDPG, submitted its final report in August 2010, including several recommendations. The panel recommended that Japan maintain its Three Non-Nuclear Principles, notwithstanding some speculation that it would recommend reconsideration of the non-introduction principle. [5] As expected, the new NDPG stipulated, "Japan will continue to uphold ...the Three Non-Nuclear Principles." [6] Despite sporadic debates over the issue of non-introduction, for the foreseeable future it is highly unlikely that Japan will change the Three Principles.

Disarmament Initiatives

Japan's commitment to nuclear disarmament and nonproliferation and its support for the NPT have remained unchanged since it acceded to the treaty in 1976. Tokyo has been further intensifying its efforts toward strengthening multilateral nonproliferation and disarmament regimes since the early 1990s. These efforts reflect a shift in its foreign policy after the Cold War in which Tokyo has been increasingly emphasizing the importance of international cooperation on disarmament and nonproliferation, and actively participating in efforts to strengthen international peace and security. Japan has submitted disarmament resolutions to the United Nations General Assembly every year since 1994, and ratified the Comprehensive Nuclear Test Ban Treaty (CTBT) in 1997 while pushing for its early entry into force. Japan has also strongly supported a Fissile Material Cut-off Treaty (FMCT). [7] Japan's Hiroshima and Nagasaki experiences, coupled with its highly developed technology sector and an economy which enables it to commit resources to international nonproliferation and disarmament efforts, have uniquely situated it to uphold and promote the principles of nuclear nonproliferation and disarmament. In particular, Tokyo has actively promoted disarmament and nonproliferation education since the United Nations General Assembly endorsed the Secretary General's report on the UN Study on Disarmament and Nonproliferation Education in November 2002. [8]

In 2008, Japan and Australia established the International Commission on Nuclear Non-Proliferation and Disarmament (ICNND) to reinvigorate international nonproliferation and disarmament efforts, and to help shape a consensus at the then-upcoming 2010 NPT Review Conference. [9] The ICNND's final report, containing 76 recommendations, was issued in December 2009. [10] While the report does not represent the official policy of Japan or Australia, the two governments are closely working together to promote nuclear disarmament and nonproliferation. They have reached out to non -nuclear weapon states to form an alliance to further promote disarmament and nonproliferation. As part of these efforts, the two countries launched the Non-Proliferation and Disarmament Initiative (NPDI) with eight other countries, including Canada, Germany, Mexico, Turkey, Chile, the Netherlands, Poland, and the United Arab Emirates. The two countries co-sponsored a ministerial-level meeting on nuclear disarmament and nonproliferation on the sidelines of the United Nations General Assembly meeting in September 2010.[11] The second ministerial-level meeting of the NPDI was held on April 30, 2011 in Berlin, Germany where it adopted the Berlin Statement urging, among other things, the immediate commencement of FMCT negotiations, early entry-into force of the CTBT, concrete progress in nuclear disarmament, and the universalization of the IAEA Additional Protocol. [12]

U.S. Extended Nuclear Deterrence

Japan's security relationship with the United States has tempered Tokyo's emphasis on disarmament, as Japan remains a beneficiary of U.S. extended nuclear deterrence. Despite its intensified nonproliferation and disarmament efforts since the 1990s, Tokyo's two seemingly contradictory nuclear weapons-related policies have complicated its efforts to champion nuclear disarmament. Japan's National Defense Program Guidelines state, "Against the threat of nuclear weapons, rely on the U.S. nuclear deterrent, while working actively on international efforts for realistic and steady nuclear disarmament aiming at a world free from nuclear weapons." [13] Critics often assert that such a statement represents the Japanese government's ultimate dilemma. However, as long as nuclear weapons threats exist, Japan's official stance acknowledges that both disarmament and extended deterrence are necessary to enhance its national security.

Increased U.S. and international interest in the nuclear disarmament process has therefore created mixed feelings in Japan, where stronger commitment to nuclear disarmament is welcomed on the one hand, while there is a cause for concern about the U.S. extended deterrent commitment on the other. The U.S. and Japan therefore in July 2009 set up an official framework to conduct periodic dialogues, including issues such as extended nuclear deterrence, in which the United States reiterated its commitments to Japan. [14] Contrary to Tokyo's official policy, both mayors of Hiroshima and Nagasaki in their Peace Declarations urged the Japanese government to pursue security without relying upon U.S. extended nuclear deterrence. [15]

Nuclear Energy Issues

Japan increasingly relies on nuclear power for its electricity needs, and has a highly developed civilian nuclear sector. With almost no indigenous energy sources, Japan's nuclear energy accounts for over 30% of the country's total electricity production. Japan had planned to increase this to 41% by 2017, and 50% by 2030. [16] However, the Great East Japan Earthquake that devastated the Tohoku region in Japan on 11 March 2011 caused a catastrophic nuclear accident at the Fukushima Dai-ichi Nuclear Power Stations of Tokyo Electric Power Co., and as a result significantly affected Japan's nuclear energy policy and public opinions towards nuclear energy. Currently, Japan has 54 nuclear power reactors across the country (the third largest number of power reactors after the United States and France), but only 11 were in operation as of November 2011.[17] Japan is in the process of constructing two new power reactors, and had been planning to construct 11 additional reactors. However, due to the Fukushima accident, Japan's nuclear energy policy is at a crossroads. Then Prime Minister Kan, in early May 2011, said that Japan would scrap plans to build new nuclear reactors since the country needs to start from scratch in creating a new energy policy. [18] He also announced at the 50th anniversary of the OECD the new policy goal of generating 20% of Japan's electricity from renewable sources by early 2020. [19] The Japanese government is reviewing the Framework of Nuclear Energy Policy, which was suspended due to the March 2011 Fukushima accident, and a new policy is expected to be issued by the end of August 2012. 

In his statement at the United Nations High Level Meeting on Nuclear Safety and Security in September 2011, Japan’s newly elected Prime Minister Yoshihiko Noda pledged further efforts to strengthen nuclear safety and security. He did not mention the possibility of the reduction of Japan’s reliance on nuclear energy, although in his inaugural policy statement earlier in the same month, Noda had highlighted that Japan should reduce its dependence on nuclear power generation in terms of a medium and long-term perspective.

As one of the most notable developments in Japan's nuclear energy policy since the Fukushima accident, the Japanese government has decided to establish a new agency in charge of nuclear safety under the Environment Ministry, given acute criticism that its current system failed to appropriately and effectively respond to, or even prevent, the nuclear crisis. Currently, the Nuclear and Industrial Safety Agency is under the Ministry of Economy, Trade, & Industry, which promotes nuclear energy. The government aims to create a new agency combining safety and regulatory functions that is completely separated from organizations promoting nuclear power. The new agency is tentatively named the Nuclear Safety Agency, and is expected to be launched in April 2012 after necessary legislative procedures. [20]

Japan has a controversial program for recycling spent nuclear fuel that has produced large quantities of plutonium in the form of metal-oxide nuclear fuel. [21] As of December 2010, Japan possessed 35 metric tons of spent fuel stored at reprocessing plants in Britain and France, along with a domestic stockpile of 9.9 metric tons. [22] All of the nuclear fuel stockpile will ultimately return to Japan for use in domestic nuclear facilities. The original plan called for consumption of the stored fuel by 2010, but due to technical and safety issues, this timetable has been delayed, and the return of the stored fuel to Japan is proceeding slowly. Some argue this material could provide Japan with a latent nuclear weapons capability. This amount of plutonium, if further processed for use in nuclear weapons, would be sufficient for approximately 10,000 warheads.

Japan's strong commitment to the development of a self-sufficient plutonium-based nuclear fuel cycle led to the construction of the Rokkasho spent fuel recycling complex in Aomori Prefecture (Northernmost prefecture of Japan's Main Island). This will be the first commercial nuclear fuel reprocessing plant in Japan, and the first one in an NPT non-nuclear weapon state. Despite strong domestic and international criticism and opposition, the reprocessing plant started active testing on 31 March 2006. Once the reprocessing plant moves beyond the testing phase to become commercially operational, it will separate and stockpile up to eight megatons of plutonium annually. The Rokkasho reprocessing plant was originally scheduled to become operational in November 2008, a date subsequently pushed back to October 2010. [23] However, complications during test operations caused Japan Nuclear Fuel Ltd. to postpone this date again by approximately two years, resulting in a new estimated operational date of sometime in 2012. [24] This is the 18th postponement so far. [25]

Although the long-term effects of the Fukushima accident remain unclear, current government policies suggest it is likely that Japan will tone down its enthusiasm to complete the nuclear fuel cycle project. Prime Minister Kan has expressed his intention to reconsider the nuclear fuel cycle project. [26] Mr. Goshi Hosono, Minister for the Restoration from and Prevention of Nuclear Accident also mentioned that in the process of overhauling the country's nuclear energy policy, its entire nuclear fuel policy, including nuclear fuel recycling facilities in Rokkasho village and the Monju prototype fast breeder reactor in Fukui prefecture, should also be reviewed. [27] Whether Japan will continue to pursue the utilization of fast breeder reactors is uncertain. Japan has long planned to develop fast breeder reactors so that it can improve uranium utilization. The prototype fast breeder reactor, Monju, is currently shut down. The shut down occurred after an accident in August 2010 that happened while the reactor was being prepared to restart operations for the first time since a December 1995 shut down caused by a major sodium leak and fire. [28]

Nuclearization Debates

Anti-nuclear sentiment among the Japanese public has far outweighed support for keeping a nuclear weapons option open. It has long been considered taboo for Japanese officials to argue in favor of the possibility of a nuclear weapons option.

Nevertheless, several neighboring countries have expressed concerns about possible Japanese nuclear ambitions due to Japanese officials' occasional nuclearization debates. Recent tension developing in the region, particularly on the Korean peninsula, has led to increased discussions in Japan about the once-taboo subject of nuclear weapons development, including comments by high-ranking officials on the possibility of amending the three non-nuclear principles in 2002. Most recently, after North Korea conducted its nuclear weapon test in October 2006, high-ranking Japanese officials made some comments advocating that the debate over developing nuclear weapons should not be prohibited. It appears that the threshold for the debate of nuclear weapons in Japan has been lowered. [29]

Still, despite speculation that Japan may reconsider its nuclear options, the Japanese public's deep aversion to nuclear weapons and Tokyo's strong commitment to international nonproliferation regimes make any move in this direction unlikely.

Sources:
[1] Yuri Kase, "The Costs and Benefits of Japan's Nuclearization: An Insight into the 1968/70 Internal Report," The Nonproliferation Review, Summer 2001.
[2] Japanese Ministry of Defense, Summary of National Defense Program Guidelines, FY2011, www.mod.go.jp.
[3] Japanese Ministry of Defense, Summary of National Defense Program Guidelines, FY2011, www.mod.go.jp.
[4] "Japan confirms secret pact on US nuclear transit," BBC, 9 March 2010, http://news.bbc.co.uk.
[5] "Japan Advised to Keep Non-Nuclear Principles," Global Security Newswire, 27 August 2010, www.nti.org.
[6] Japanese Ministry of Defense, Summary of National Defense Program Guidelines, FY2011, www.mod.go.jp.
[7] "Japan's Disarmament and Non-Proliferation Policy," 4th edition, Japanese Ministry of Foreign Affairs, March 2008, www.mofa.go.jp.
[8] "Disarmament and Non-Proliferation Education: Promoting Cooperation with Civil Society Towards a World without Nuclear Weapons," Joint Working Paper Submitted by Japan and the United Nations University at the 2010 NPT Review Conference. www.un.org.
[9] International Commission on Nuclear Nonproliferation and Disarmament, www.icnnd.org.
[10] "Eliminating Nuclear Threats," ICNND Final Paper, December 2009, www.icnnd.org.
[11] "Nonnuclear nations seek bigger say via alliance," The Yomiuri Shimbun, 22 July 2010, www.yomiuri.co.jp.
[12] "The 2nd Foreign Ministers' Meeting on Nuclear Disarmament and Nonproliferation: Setting Out Concrete Proposals for the Reduction of Nuclear Risks," Japanese Ministry of Foreign Affairs, 30 April 2011, www.mofa.go.jp.
[13] "National Defense Program Guidelines, FY 2005," Japanese Ministry of Defense, www.mod.go.jp.
[14] Kyoko Hasegawa, ""US, Japan agree to set up official talks on nuclear deterrence," in Lexis Nexis, 18 July 2009.
[15] Hiroshima Peace Declaration, Hiroshima Peace Cite, www.pcf.city.hiroshima.jp, Nagasaki Peace Declaration, Nagasaki City- Peace & Atomic Bomb, www1.city.nagasaki.nagasaki.jp.
[16] "Nuclear Power in Japan," World Nuclear Association, www.world-nuclear.org.
[17] Chikako Mogi, "Analysis: Energy Policy Chaos Threatens Japan's Economy," Reuters, 4 August 2011, www.reuters.com.
[18] "Kan Slams Nuclear Energy, Goes Green," Asahi Shimbun, 11 May 2011, www.asahi.com.
[19] Address by H.E. Mr. Naoto Kan, Prime Minister of Japan, at the Commemoration Ceremony of the 50th Anniversary of the OECD 25 May 2011, www.kantei.go.jp.
[20] "Independent N-power Agency Eyed: Body would Consolidate Oversight Roles," The Daily Yomiuri, 4 August 2011.
[21] Nuclear Power in Japan," World Nuclear Association, www.world-nuclear.org.
[22] Global Fissile Material Report 2010, IPFM, www.fissilematerials.org.
[23] "Nuclear Power in Japan," World Nuclear Association, www.world-nuclear.org.
[24] "Rokkasho plant faces two-year delay," The Japan Times, 2 September 2010, www.japantimes.co.jp.
[25] "Gennen Shiuunten Shuuryou wo Ninen Enki he [JNFL extends test operation for 2 more years]," The Asahi Shimbun, 2 September 2010 (Japanese), http://mytown.asahi.com.
[26] "Kan Calls for Spent Nuclear Fuel Review," Jiji Press Ticker Service, 16 May 2011. www.leisnexis.com.
[27] "Land Decontamination Key to Enabling Evacuees to go Home: Hosono" Japan Economic Newswire, 27 July 2011. www.lexisnexis.com.
[28] Global Fissile Material Report 2010, IPFM, www.fissilematerials.org.
[29] "Nuclear Logic Fails," The Japan Times, 19 October 2006.